Using approximately 1500 mice six months of age or older, do the following: evaluate combinations of chemotherapy and chemoradiotherapy for treatment of spontaneously occurring leukemia-lymphoma and for inducing immunosuppression; admission of H2 incompatible immunocompetent cells to the immunosuppressed lymphoma-leukemia animals; monitor graft-versushost reactions and their effects on tumors bore; evaluate chemotherapy or chemoradiotherapy and antiserum against H2 incompatible cells plus administer immune H2 compatible bone marrow to rescue from graft-versus-host reaction; keep records of survival and disease states; and perform experiments to evaluate effects of nonspecific illness and debilitation on tumor system.